1. Field of the Invention
The invention relates to a radiation image capturing device and a radiation image capturing system and more particularly, to a radiation image capturing device and a radiation image capturing system, each including a radiation image capturing unit.
2. Description of the Related Art
In recent years, interventional radiology (IVR) has rapidly spread in medical treatment is performed by inserting a catheter having a tip end mounted with various instruments into a body of a patient, making the tip end of the catheter arrive at a lesion part of the patient's body while monitoring a state of the body of the patient in real time on the basis of a radiation image displayed on a monitor, and operating the catheter at the outside of the body.
A technician performs a medical treatment while observing a radiation image displayed on a monitor at the time of executing IVR. Accordingly, as treatment time increases, a patient is exposed to a larger dose of radiation.
Japanese Patent Application Laid-Open (JP-A) No. 2008-220480 discloses a radiographic imaging device that can capture a radiation image by automatically setting an irradiation range and therefore a radiation irradiation condition depending on the position of a treatment instrument inserted into a subject to thereby reduce an exposure dose with respect to the subject. The radiographic imaging device includes a radiation detector in which plural radiation detecting elements are arranged two-dimensionally, and irradiates radiation emitted from a radiation source onto the radiation detector through the subject to capture a radiation image. The radiographic imaging device includes an instrument detecting unit that processes the radiation image captured by the radiation detector and detects the treatment instrument inserted into the subject, a position calculating unit that calculates the position of the detected treatment instrument in the subject, and a setting unit that sets the irradiation range of the radiation including the treatment instrument according to the calculated position of the treatment instrument in the subject and sets the radiation irradiation condition with respect to the irradiation range, and captures the radiation image within the set irradiation range according to the set radiation irradiation condition.
JP-A No. 5-161639 discloses a radiographic imaging device for selecting an optimal adjusting unit according to an imaging part in control for adjustment of an irradiation dose based on detection of a transmission dose. The radiographic imaging device detects a dose of radiation transmitted through an object by scanning and operating a radiation fan beam, and captures a radiation projection image. The radiographic imaging device includes a transmitted radiation dose detecting unit that has plural detecting elements arranged in a longitudinal direction of the radiation fan beam and outputs a detection signal according to the dose of radiation transmitted through the object for each detecting element, a first radiation dose adjusting unit that arranges plural radiation shielding members, the number of which is equal to the number of detecting elements, in the longitudinal direction of the radiation fan beam and adjusts a radiation transmission opening area at plural points in the longitudinal direction of the radiation fan beam by displacement of the plural radiation shielding members, a second radiation dose adjusting unit that arranges plural wedge-type radiation attenuating members, the number of which is equal to the number of the detecting elements, in the longitudinal direction of the radiation fan beam and adjusts a radiation attenuation rate at plural points in the longitudinal direction of the radiation fan beam by displacement of the plural wedge-type radiation attenuating members, and a radiation dose control unit that controls an operation of at least one of the first radiation dose adjusting unit and the second radiation dose adjusting unit on the basis of the detection signal from the transmitted radiation dose detecting unit and changes and adjusts the dose of radiation of the radiation fan beam irradiated onto the object.
JP-A No. 11-142597 discloses a movable compensation filter device that has a compensation filter capable of being used in plural imaging parts. The movable compensation filter device includes two compensation filter pieces and a filter moving unit to support the compensation filter pieces and move the compensation filter pieces in parallel. In the movable compensation filter device, each of the compensation filer pieces has a flat shape and is made of an X-ray absorbing material in which the thickness thereof varies depending on place. A combination of a left part and a right part or a combination of the right part and the left part of each of the two compensation filter pieces constitute one compensation filter for a single imaging part.
JP-A No. 2005-27823 discloses an X-ray imaging device for reducing an exposure dose with respect to a subject and imaging a target part and a peripheral region thereof with a desired image that is required for medical treatment and diagnosis to permit observation of the target part and the peripheral region. The X-ray imaging device includes an X-ray generating unit that irradiates X-rays onto the subject, a diaphragm unit that determines an X-ray irradiation field, and an X-ray detecting unit that detects the X-rays irradiated from the X-ray generating unit. An X-ray absorbing filter that absorbs the X-rays is disposed at least one of the X-ray generating unit side or the X-ray detecting unit side of the diaphragm unit, regions where the X-ray dosage and X-ray energy vary are formed in the irradiation field by a function of the X-ray absorbing filter, and image information is obtained by the X-ray detecting unit.
JP-A No. 5-329138 discloses an X-ray scanning device for substantially equalizing a flux of an X-ray fan beam over the entire length of the fan beam. The X-ray scanning device includes an X-ray source that generates the X-ray fan beam and scans an object with the fan beam, a detector including a detector row that detects the X-ray flux transmitted through the object at plural points crossing the fan beam and that is disposed to correspond to the fan beam at an opposite side of the object to output an electric signal indicating the flux detected at the plural points, an X-ray flux modulator that uses a wedge-type shutter which modulates the flux density of the fan beam at the plural points crossing the fan beam, and a feedback circuit that controls the modulator on the basis of the output signal of the detector row to modulate the flux of the fan beam at the plural points crossing the fan beam, and causes the flux of the fan beam detected by the detector row to be substantially equalized over the entire length of the fan beam.
JP-A No. 2005-198762 discloses an X-ray diagnostic device which includes an X-ray generating unit that irradiates X-rays onto a subject, an X-ray detecting unit that detects X-rays irradiated by the X-ray generating unit and transmitted through the subject, an image data generating unit that generates X-ray image data concerning the subject on the basis of the X-rays detected by the X-ray detecting unit, a display unit that displays the generated X-ray image data, a dose detecting unit that detects a radiation dose of the X-rays irradiated from the X-ray generating unit, an irradiation dose calculating unit that calculates an irradiation dose for the subject on the basis of the radiation dose detected by the dose detecting unit, an irradiation dose comparing unit that compares the irradiation dose calculated by the irradiation dose calculating unit and a predetermined allowable irradiation dose, and a dose control unit that controls the radiation dose of the X-rays by the X-ray generating unit on the basis of the comparison result obtained by the irradiation dose comparing unit.
JP-A No. 2001-17416 discloses an imaging device which includes an imaging unit that captures an image of a subject by radiation and acquires image information on the subject, a setting unit that sets information on a kind of a generation source of the image information obtained by the imaging unit, an attribute of the subject, and an imaging part of the subject, a reducing amount determining unit that determines the reducing amount of radiation on the basis of the information set by the setting unit, and a reducing control unit that controls reducing of the radiation on the basis of the reducing amount determined by the reducing amount determining unit.
JP-A No. 2008-119195 discloses an X-ray imaging device which includes an X-ray generator that intermittently irradiates X-rays onto a subject and an X-ray detector that acquires image data according to an incidence dose of the X-rays transmitted through the subject. The X-ray imaging device includes a dose control unit that controls the irradiation dose of the X-rays to the subject and controls the X-ray irradiation so as to repeat a combined irradiation pattern of irradiation with a regular dose and irradiation with a dose smaller than the regular dose.
JP-A No. 2008-272381 discloses an X-ray imaging device which includes an estimation unit that estimates a cumulative exposure dose of X-rays irradiated onto an object, a remaining exposure tolerance dose calculating unit that calculates a remaining exposure tolerance dose using a difference between a tolerated maximum exposure dose and the cumulative exposure dose, an X-ray irradiation tolerance time calculating unit that calculates an X-ray irradiation tolerance time using a difference between a predetermined X-ray irradiation scheduled time and an actual irradiation time of X-rays irradiated onto the object, an X-ray irradiation reference dose calculating unit that calculates an X-ray irradiation reference dose per unit time that is a reference of X-ray irradiation, on the basis of the remaining exposure tolerance dose and the X-ray irradiation tolerance time, and a control unit that controls X-ray irradiation on the object by setting an X-ray irradiation dose per unit time within the X-ray irradiation tolerance time, on the basis of the X-ray irradiation reference dose.
JP-A No. 2009-160308 discloses a radiation treatment system which includes an irradiating unit that irradiates a treatment radiation beam according to an irradiation plan that determines an irradiation condition of radiation on the basis of a reference dose absorbed by a treatment part and a normal part of a subject, a detecting unit that detects scattered rays generated on the basis of the treatment radiation beam, an acquiring unit that acquires data of an absorbed dose from data of the detected scattered rays, a calculating unit that calculates a dose distribution including irradiation and non-irradiation on the basis of the absorbed dose data and the irradiation plan, an evaluating unit that evaluates whether the irradiation plan is appropriate or not using a predetermined evaluation reference on the basis of the absorbed dose data, and a providing unit that provides the dose distribution and the evaluation result.
JP-A Nos. 2007-97909 and 2009-213905 disclose a radiation exposure dose managing system in which a radiation inspecting device, an image managing server, an exposure dose managing device, and an in-hospital information database server are connected to one another via a network. The image managing server holds images of parts of a body of a subject captured by the radiation inspecting device and an image information group including a variety of information related to capturing of the images. The exposure dose managing device manages data of an exposure dose with respect to the subject when the image is captured by the radiation inspecting device. The in-hospital information database server manages personal information of the subject. In the radiation exposure dose managing system, the exposure dose managing device has a function of extracting information, which is necessary to calculate the exposure dose, from the image information group held in the image managing server, and calculating the exposure dose on the basis of the extracted information. In addition, the data of the exposure dose that is calculated by the exposure dose managing device is transmitted to the in-hospital information database through the network and is recorded and stored in a personal information database for the subjects in the in-hospital information database.